Potential role of bioactive compounds of Phaseolus vulgaris L. on lipid-lowering mechanisms

Highlights

• Common beans consumption attenuates hypercholesterolemia and hyperlipidemia

• P. vulgaris can reduce food intake and regulate neuropeptides signaling hunger

• Bioactive compounds of P. vulgaris are able to modulate hepatic lipogenic enzymes

Abstract

Common bean (Phaseolus vulgaris L.) is an important source of phytochemicals with hypolipidemic properties. Since hyperlipidemia is involved in the development of several chronic diseases, the lipid-lowering feature becomes an attractive property. This review focuses in research that has been conducted in vivo and in vitro experiments about specific bioactive compounds and the proposed mechanisms of action on serum lipids reduction. The hypocholesterolemic effect of beans has been associated with their dietary fiber and resistant starch content. The mechanism of action includes inhibition of intestinal lipid absorption, binding of bile acids, increase of fecal cholesterol excretion and a putative effect on hepatic low-density lipoproteins receptor for improved lipoproteins clearance. Short-chain fatty acids, produced by the fermentation of bean fiber and resistant starch, along with phytohemagglutinin have the ability to regulate appetite and satiety, activating gut hormones receptors and modulating orexigenic neuropeptides such as ghrelin, and anorexigenic neuropeptides such as glucagon-like peptide-1, peptide tyrosine–tyrosine and cholecystokinin. Other phytochemicals such as phytosterols and saponins reduce absorption of lipids at intestinal level by binding of bile acids, cholesterol micelles disruption and downregulation of lipogenic proteins via the liver X receptor pathway.

Introduction

Lipid alterations play a significant role in the etiology of several chronic diseases, including obesity (Couillard et al., 1998, Klop et al., 2013), cardiovascular (Boekholdt et al., 2012, Hosseinpanah et al., 2014, The Lipid Research Clinics Coronary Primary Prevention Trial results. I, 1984), hepatic (Orešič et al., 2013, Speliotes et al., 2010), and renal diseases (Bagdade et al., 1978, Kronenberg, 2005, Kronenberg et al., 2002). Hyperlipidemia is a common disorder found in western societies. It is defined as an imbalance in blood lipids homeostasis characterized by elevated levels of lipids or lipoproteins (LPLs) in serum/plasma, being high total cholesterol and high triglycerides the most common conditions (Stone et al., 2013).

Currently, it is known that a wide variety of phytochemicals exerts physiological effects on lipids metabolism. In this sense, dietary prevention strategies against hyperlipidemia have gained interest (Kwon, Apostolidis, Kim, & Shetty, 2007).

Common bean (Phaseolus vulgaris L.) is one of the most important legumes consumed worldwide. Beans are an excellent source of protein, carbohydrates, dietary fiber (DF), vitamins, minerals and phytochemicals (Tharanathan & Mahadevamma, 2003). Carbohydrates are the major constituents of beans, their content in the seed range from 50% to 76% depending on the variety (Barampama and Simard, 1993, Campos-Vega et al., 2009, Vargas-Torres et al., 2004). Starch is the predominant component of carbohydrates, which represents 32% to 52% (Eyaru et al., 2009, Ramírez-Jiménez et al., 2014); along with DF, with levels from 15% to 45% (Campos-Vega et al., 2009, USDA Critical Reviews in Food Science and Nutrition National Nutrient Databank for food composition, 2004, Vasić et al., 2009). The protein content in the dry seed varies significantly among cultivars, ranging from 17% to 30% (Hayat, Ahmad, Masud, Ahmed, & Bashir, 2014).

Moreover, common beans are a rich source of bioactive compounds that promote several beneficial effects for human health. The most relevant phytochemicals of this legume comprise phenolic compounds, which are linked to antioxidant activity, antimutagenic and anticarcinogenic effects (Campos-Vega et al., 2013, Campos-Vega et al., 2009, Cardador-Martinez et al., 2002, Feregrino-Pérez et al., 2008, Paredes-López et al., 2006, Vergara-Castañeda et al., 2012); non-digestible polysaccharides and enzyme inhibitors with low glycemic index (Celleno, Tolaini, D'Amore, Perricone, & Preuss, 2007) and bifidogenic potential (Queiroz-Monici, Costa, da Silva, Reis, & Oliveira, 2005); bioactive peptides with antihypertensive properties (Luna Vital, González de Mejía, Dia and Loarca-Piña, 2014, Luna Vital, Loarca-Piña, Dia and González de Mejía, 2014); as well as, saponins and phytosterols with proven hypolipidemic benefits (Han et al., 2003, Marzolo et al., 1993, Moundras et al., 1997).

Particularly, common beans have been considered as hypolipidemic agents due to their cholesterol-lowering properties (Han et al., 2003, Han et al., 2004), food intake reduction (Fantini et al., 2009, Nilsson et al., 2013, Spadafranca et al., 2013) and inhibition of intestinal lipid absorption (Chávez-Santoscoy et al., 2013, Chávez-Santoscoy, Tovar, Serna-Saldivar, Torres and Gutiérrez-Uribe, 2014, Han et al., 2003, Han et al., 2005).

This review focuses on experimental evidence that supports the role of phytochemicals of P. vulgaris on the most relevant biological mechanisms (direct or indirect) involved in circulating lipids lowering.